Gun recoil mechanism



June l, 1948. D. l.. MEYERS ETAL 2,442,37l

I GUN RECOIL MECHANISM Filed March 1s, 194e ATTORNEYS Patented June 1,1948 UNITED STATES PATENT oFFicE GUN RECoIL MECHANISM VDonald L. Meyersand Arnold A. Kester, Rock Island, Ill., assignors to the United Statesof America as represented bythe Secretary of War.

Application March 18,` 1946, Serial No. 655,353

(Granted under the act of March 3, 1883, as' amended April 3Q, 1928;A270 O. G. 757) 7 Claims.

in counterrecoil, .or return to battery. In its specific. aspects, theinvention pertains to improvements in the buer means in a recoilmechanism v.of `the concentric type, one example of which is shown inthe United States Patent to Lucht, No. 2,358,340.

Recoil mechanisms of the concentric type are particularly adapted foruse inarmored vehicles, turrets .and the like and comprise .basically .agun tube encased in and slidably carried by a concentrically arrangedsupport having lan Aannular elongated .chamber containing the recoiliiuid and the recoil .spring and piston mechanism. A particular problemattendant uponthe design, constructionand use of recoil mechanisms ofthe concentric .ty-pe is that which arises from the requirement that themechanism for bufling the counterrecoll stroke of the gun be locatedwithin the recoil fluid chamber. This requirement necessarily means thatthe buing mechanism must :be simple in construction, eicient inoperation and comprising relatively few movable parts.

The present invention contemplates and has for itsprincipal object theprovision of a recoil mechanism of the Vconcentric type having animproved buing means in which the cooperable parts are respectivelyformed on basic stationary and movable parts of the recoil mechanism.

It is an important object of the invention to provide a buing means inwhich the cooperable parts are so formed and so arranged with respecttoeach other as to check eiiiciently the action of thegun in its finalphases of counterrecoil, this result being accomplished by forming onebuier tionof a cone diminishing in the direction of recoil, and a secondbuffer element as a, sleeve having an inner, substantially cylindricalperiphery variably cooperable .with the conical periphery of theiirstbuier element as the gun completes counterrecoil.

Itis another object of `the invention to provide in conjunction with thebuffer elements a proximate .annular recess .or reduced cylindricalportion which `cooperates with the buffer sleeve to provide, just priorto completion of counterrecoil, a buier pocket within which recoil uidmay be trapped and from which the recoil fluid .may .beeXhausted-by-cooperation of the cylindrical buffer sleeve Ywith the`conical or tapered buler element.

Other objects and features of the invention will become apparent tothose skilled in the art as the disclosure is more fully made in thefollowing detailed description of apreferred embodiment of the inventionas illustrated in the accompanying sheet of drawings in which:

Fig. 1 is a side elevational view, partly in section, of theintermediate portion of a -gu-n mount and recoil mechanism havingincorporated therein a preferred formof bufng Ameans constructedaccording to the present invention, the parts =be ing shown in thepositions occupied thereby when the gun is in battery and the gun tubebeing illustrated diagrammatically;

Fig. 2 is a fragmentary longitudinal sectional view of the upper frontportion .of the recoil mechanism and gun tube and illustrating theposi.- tions of the parts just priorrto ,completion Yof counterrecoil;and- Fig. 3 is a transverse Sectio `al yiew `taken sub- Although theinvention has been illustrated .and described in connection with thepreferred em.- bodiment thereof and in conjunction with a par.-

, ticular type ofsrecoil mechanism, it should Abe Yap.-

element with an outer periphery having the secpreciated that theinvention may assume other forms and may be otherwise adapted.Accordingly, the present disclosure should be taken as illus.-trativeand not limiting. Y A

The particularA type" of ,gunfand Amou-nt chosen for the purposes .ofillustration includes va .cylindrical or tubular member'or .cradle i0formed at its forward or counterrecoil V end vllil'fh an externalannular Vflange l I and ,at its rear or recoil end with an integralVbracket structure l2 includinga longitudinally.forwardly extendingsupporting Yportion i3 .and Aa rear ilange i5.' The flange Il at the'forward or counterrecoil end of the v cradle .cylinder Il) serves .asmeans by which .the mechanism 'may be. adequately supported Vin a gunmount, a portion oi such .mount being .illustratedat IB as beingsecuredbyla plurality'of cap screws I1 to the ange Ill.V "Thereariiange l5 islikewiseadapted tosllpport the gun in .a Suitable mount. A portion Aofsuch mount `is indicatedjby the numeral I8 and is shown as including afront flange i9 secured by a plurality. of bolts 2 0 to .the flange 15.I

' The cradle 1 0 of composite construction and comprises a double.cylinder supporting structure having aninner hollow cylinder or tubularmember 2| and van outer hollowcylinder o r tubular member or support122.'."The forward end of .the inner tubular member v1lis'formedasanannular radial wall V23 forme d at its peripheral edge witha rearwardlyextending threaded cylindrical portion24. The vouter'":ylindrical member '2 2 is internally threaded as at zs i.v and tne.Vjmreadcd portionsl2iland25 are'screwedtQgether to provide arigid.connection.betweenfthe two tubular members2l' and 2 2.

3 The inner tubular `or-cylindricalfmember 2| is provided at axiallyspaced points along its interior with a plurality of annular interna1bearings 26 which serve to mount a gun tube 21 in j the cradle l0. Therelationship between the gun tube 21 and the cradle l0 is such that'thetube' may reciprocate in recoil and counterrecoil. `The forward end ofthe gun tube 21 pro'jegcts through g the front radial wall 23 ofthevinner tubular member 2| and suitable packing 28 isprovidedat thispoint in the radial wall 23 for cooperation with the outer periphery ofthe gun tube 21 to 'provide means guarding against the entrance of Ydirtand other foreign matter to thebearings 26. j

The rear or recoil end of th'e gun tube 21 extends axially beyond therearward end of the cradle-,structure 10, atwhich point the gun tube isprovided`r with fan annular radial: iiange 29 '(shownY"diagrammatically). Ajrecoil sleeve -or tube 3i] Vencircle's]and`i'sslidablyarried bythe outer peripheryfof the-inner tubularmember 2 I.This sleeve, like the gunftube-21, projects axially atthe rear forrecoil endofthe-cradle IEI and -at that Ypoint is provided with'anexternally Ythreaded end portion- 3H Aninternally threaded ring 32 isthreadedon thee'nd portion- 3Lv The ring 32 is also threaded externallyasA at 33 and receives an internally threaded; portion-34 ofa securingring 35. The ring` 35 includesfan'annular cylindrical portiony on which`the'internal` thread 34 isformed, and anintcgra-lannular radially ,in-Vwardly extending angre 36 v'vhihfcooperates -with lthe flange 29 ofthev gun tubev21 toficonnect the gun tube 21 rigidly tothesleevevf30f4sothat ,these 'parts move in-unisonin recoil ,and,counterrecoil A locking screw 31 -cooperatesubetween the ring 32 andthe'end portionl'ot fthesleeve A3l) for preventingV looseningv ofVV the1 parts.- A locking 'screw 38 is carried bythering gandis engageable Ywith the exterior or thejring32 for: preventingloosening` ofthcsejparts.`IQi'lievforward portonofjthe ring 32 Vis 'formedf as a radiallyoutwardly extending annularv iiange 39 on whichl is rigidly mountedannular sheetmetal shield 453. This shieldservesV tognlinimize theprobability of the entrance of du into the mehaniSm; v

The rear orjrec'oilV end ott/he' outer cylindrical orV tubular member"22 is internallyjthreaded, as atf4l, and receivesaniexternallyjthreaded closure ring-42.` .1 vThe .ring 42 is provided atits Y. interior with a .suitable packing ring :43 Vwhich `provides a.seal. between the; ring V42 ,Y and the"V exterior 'of the recoil sleevev3U; A, similar .packing V,ring 44 is carried by the recoil end of theinner cylindrical or tubular,t member .2;l and cooperates between thatmemberrand the interiorlof the recoilsleeve v30. V.'lhese packingringsmay be of, any conventional' type andserve'toprevent the escape ofrecoil iiuid andalso the ,entrance `of vdirt,`grit, etc., to therecoil,mechanism..1 j i, The relationship between the inner andV outertubular members 2l and 22 .is such that jthere, is providedtherebetweenV 1, an., elongated annular chamber 45 which maybontain anysuitable recoil iluid such as -theusual recoil oil.AV The closurebetween the members 12| andrv 2,2 ,affordedby the Vradial end wall 23is:fluidtight,v as is the closure atorded at the recoil end vofthe'cradleby the relationship between the. closure ring 42, threadedportiont4l of the outer tubular member 22 and packing-43 betweenth'ering 42` and recoil sleeve 39.Y The .interior ci"V the'outertubularmemberj r22 is provided .with ajplurality ofv longitudinally, runningcircumferentlally spaced fluidgor.; oil grooves st` ,and other foreignmatter 1- 4 46 which, as best shown in Fig. 41, vary in depth throughouttheir lengths. The'function of these grooves in conjunction with theaction of the gun 'in recoil and counterrecoil will be explained below.wjhe outer Dtubular or cylindrical member 22 is Yprovided-eat' itsrecoil end with a. filler opening 41, normally closedby-a Iiller plug48. i 4The recoil sleeve is provided near its counterrecoil end withAa.l ring piston 49. In the present case this pistonis shown as aseparate component rigidly securedto the recoil sleeve by apluralitygkoflocking screws 50 (only one of which is shown). The .piston49 and the portion of the recoil sleeve 30 onwhich it is mounted areappropriately-intertted so that thrust on the piston is taken directlyby the. sleeve 3U and not by the locking 4screws 5.0.1....Rearwardly of.'the'.pistong49 the 'recoi1t.sleeve; 3B zis encircled .by andcarries anabutment ring 5.1L 1A nounterrecoil. compression spring 52encircles.thesrecoiljsleeve=301zand at. one end abuts the abutment;ring.; 5 I: Landzfat its" .otherend' .abuts ahardened' radial. ring5,3.. that faces againsttheinner radial .facerjof the :rear closure'ring.; 42. AAs .is '..usual` when. the .weapon 25 is cred, thelgunztube2.1 slides. in..the 'bearings i A26 lof "thelinner.Lotiibulanlmemberi :21 .inrlriecoil against the: counterrecoili-springZ and against therecoil. fluid. in thegchamber 45.:` :The compression spring 52'storesenergyA upon recoil'and serves to return the gun tube in counteirecoilto'fbattery. It is .characteristic of gunsxniountedior recoil andcounterrecoil. .thati variationsV occur' iri the travel ofthe gun'tubethroughzitslvarious phases of. recoil y an'dlcounter'recoil: In the.`event` that 85 these variations are noti'adequately` controlled, seriousda'rnageft the'. weapon may result.' 1 Such damage is `particularlylikely4 if; forlexainple; the weapon isallowedtoreturn violentlyv tobattery. Consequently,.it 'i's'ldesirable that the nal phases of:counterre'coilactioribe checked'or bufledf-'At theu'sameltime', itis'desirablethat-the weapon be permitted Lto' return toi battery` asrapidly as possiblegfsince sucnresult vis consonant with rapiditv'ff f'f -Accordingjto thepresentjnvention the means for checkingv orllouiiiin'g the final i phases' of lcounterrecoil, so that the gun i seased into ba-tte'lr'y,A comprises a pairl o'fcooperable -buing elementsso7constructedandl Varranged lias] -to lprovideffor the trappingof aportion f'the-r'ecoil-uid anda variable exhausting of Lthis uid betweenthe pair or" buiing Yelement'sas' the eaponcompltesfits counterrecoilaction uI njt e 'preferred l embodimentjof the'inventonshown inthedrawings, the rstibuffer lelement is designated ,generally jby thenumeral 5Y4 -andinclfud es` an; integral annular enlarged portion crmdat the -cjnterrecoil end ciY Vthe exterior oi ,theY innei-, tubularmember j 2 I. This bufferelement includes ,a rstf annularpor- OIL55.1.'@1alVe1XShQtjn @Xialxnl'cj and. af 569' onddbufng portion 5 6which extends rearwardly from .the portion 15.5;and'has.itSfutrfreiPhery tapered. 0r. formed; 'as a. frusteiclenfel .1S fediminishing in, diameter. rearwardlv.. mi; mitte direction of recoil.vAdjacent the rearpri'reoil endY of., the. conicalrianered buffer; DillonL56 forming apartojlth'egbuier elementi the exterioz;otheiinneritubularmember 2 l jlsgrooved 0f cui .Outi'bfydeen annuler receslsi 5.14 'whichprovides` in. effect a ylindricalportiou 9i' reduced diameter.extendineirearwardly ,from the., second when the gun is in battery,closely encrcles the conical surfaceor #second bufiing portion 56 of theibuffer element '54. It will be noted that the extreme forward orc'ounterrecoil portion of the buffer sleeve Y58 has an inner peripherythat has a relatively close rit with the annular portion 55 on theIbuffer elementI 54 when the 4gun is in battery. At its juncture withthe recoil sleeve 3|), -bu'fer sleeve 58 'is reduced internally to adiameter Vapproximate-ly the same as the 4external diameter 4of tubularmember 2l, to thereby form an annular radial wall or `shoulder 59 ofrelatively short radial extent. This radial wall or shoulder cooperateswith the buffer sleeve 58 and annular recess 51 to `provide a bufferpocket for the trapping of a portion of recoil uid as the gun tubeapproaches battery Yposition on completion of counterrecoil.

In the operation of the gun described herein, recoil occurs in the usualmanner after the Weapon is red and the gun tube 21 and its connectedrecoil Asleeve 30 lare driven rapidly rearwardly against thecounterrecoil spring 52 and against the coil in the chamber 45. Becauseof the cooperation Abetween the ring piston 49 and the longitudinalgrooves 46 in the interior of the outer tubular 'member 22, the oil is'throttled insuch ajmanner that the initial action of the gun in recoilis relativelyrapid and increases in rapidity until a Apoint vnear theend of the recoil stroke, at which point the throttling grooves 46 areof reduced depth and serve to further restrict the flow of oil forwardlyover the periphery of the ring piston 49.` This construction andfunction prevents jarring of the weapon as the gun reaches maximumrecoil position. spring 52 is placed under compression and after the endof the recoil stroke is reached the spring 52 reacts to drive the guntube forwardly in counterrecoil, Because of the forward tapered face onthe piston 49, counterrecoil action will be relatively rapid, whichresult is desirable from the standpoint of returning the weapon tobattery as quickly as possible so that it may be fired again. However,it is undesirable thatthe gun be permitted to slam back into battery.

As the gun tube 21 and recoil sleeve 30 reach the final pha-se 'ofcounterrecoil (Fig. 2), a relatively small portion of recoil oil istrapped in the pocket formed by the inner periphery of the During recoilthe buier sleeve 58 the radial wall or shoulder 59,

and recess 51. creases in volume as 'the recoil sleeve 30 approachesbattery position, oil trapped therein will now be forced 'out betweenthe proximate edges of the buffer element 54 and buffer sleeve 58. As'the buffer -sleeve 58 continues forwardly in counterrecoil, itYcooperates with the conical surface 56 to gradually reduce the areathrough which the trapped oil may escape from the buffer pocket.Consequently, movement of the gun tube 21 and recoil sleeve 30 will begradually slowed as the gun reaches battery and the gun will be easedinto its iinal postion as the forward end of buiier sleeve 58 slips overthe annular portion in closely tting relation therewith.

It will be seen from the foregoing description that the vbuiiing meansprovided' according to the present invention adequately checks the iinalstage of counterrecoil and absorbs the iinal shock of the weapon as thegun 'returns to battery. It will also be noted that this desirableresult is achieved by the two simple elements that are formedrespectively on a stationary and a moving part of the assembly. It willbe appreciated,

Since the aforesaid pocket desupport and within be modified 'to suitdile'ren't requirements. It

will be understood, of course, `that various other alterations andlmodifications may be made in the preferred form o'f the inventionillustrated herein without -depa'rting from the spirit and scope vof theinvention as defined in the appended claims. v

What is claimed is: l 1. Recoil mechanism :for a gun, comprising:

a double `cylinder support including .an innerl hollow cylinder and 'anouter -hollow Ycylinzler concentrically .arranged with the outerperiphery of the 'inner cylinder lspaced radially from the innerperiphery -of the vouter cylinder togprovide an annular, elongatedVchamber for containing recoil uid; Aa gun tube slidably carried withinthe inner cylinder for recoil and counterrecoil; a cylindrical sleeveldisposed concentrically between the lcylinders Vand extendingexteriorly thereof at the recoilend-of each; means `connecting thesleeve at Vits recoil end to the gun. tube for recoil Zand counterrecoiltherewith; an .integral, annular enlarged `portion formed 'on the outerperiphery of the inner cylinder at its icounterrecoil end and providing,within lthe chamber, a, concentric 'buffing element having `its Jiouterperiphery `formed Ia's 'a section of -a cone diminishing `in thedirection of recoil; means forming an annular recess in the outer`periphery ofithe inner cylinder ladjacent the -buiing element at-therecoil side thereof; and a concentric bulierring formed on thesleeve at its counterrecoil end within the chamber and including vagenerally cylindrical inner periphery having a diameter slightly greaterthan the largest diameter of theconicai buffer element "and extending inthe direction'offrecoil and positioned 'to encircle .the builer element,when the gun'tube isinv battery, and tojmove ,away from andto return tothe Vbuffer member 'upon recoil and counterrecoil of the .gun tube, thebuler ring 'forming with the vannular, recess, at a point incounterrecoil 'just prior to completion thereof, an annular 'bulerpocket.

2. Recoil mechanism for a gun, comprising: a gun tube; a tubular supportencasing the gun tube and mounting the gun tube 'for recoil andcounterrecoil; means between lthe outer peripheryof the gun tube and theinner .periphery of the tubular support formingan annularchamber forcontaining recoil fluid; means on the tubular the chamber at theA recoil.end thereof forming .an annular .concentric 'buffer element having itsouter periphery formed .as a

section of a cone diminishing inthe direction .of recoil; means on thebuiier element, at therecoil side thereof, forming an adjacent coaxial.ring portion of a diameter smaller than the smallest diameter ofthe'bulier element; and la concentric buffer sleeve encircling andconnected to `the gun tube for m'ovementtherewith in recoil andcounterrecoil and positioned in the Chamberlin .concentricity with the'buffer element, the buier sleeve having a generally cylindrical innerpe-` ripherythat closely encircles the buffer .element whenthegumtube'isin battery and'orms with the adjacent ring portion, just prior tocompletion of counterrecoil, a buer pocket adapted to trap recoil fluid.

7 1 .32; .Recoil .magwien fetta; alla .eeempeieg a a `tubularsup ort.encasing the. gun

ing in the direction of recoil ,and an adjacent' coaxial annular portionof reduced vdiameter at the recoil side ofthe .buier element; and abuier sleeve encircling land connected to the gun tube for recoiland`counterrecoil therewith and positioned in the chamber to closelyencircle the buier element when the gun tube is in battery and tovariably encircle the buffer element as the gun tube completescounterrecoil, the buler sleeve cooperating with the annular reducedportion to provide a buier pocket just prior to completion ofcounterrecol of the gun tube.

4. Recoil :mechanism for a, gun, comprising: a gun tube; a tubularsupport encasing the ,gun tubev and mounting the gun tube for recoil andcounterrecoil; means between the outer periphery of the gun tube and theinner periphery of the-tubular support forming `an annular chamber forcontaining-recoil fluid; .means within the chamber'forming a coaxialannular extension of the tubular support projecting from the counter',-recoil end ofthe chamber toward the recoil end thereof and encirclingthe-gun tube, the extension including a buffer element having an outerperiphery formed as a section of a cone diminishing in the direction ofrecoil and further including means forming anl adjacent coaxial annularrecess at the recoil. sideofthe buler element; and a, buier Ysleeve.encircling and connected to the gun tube for recoil and counterrecoilthere- With and positioned in the chamber to closely encircle the buiTerelement when the gun 'tube is in battery and to vvariably encircle thebuffer element as vthe gun tube completes counterrecoil, the buffersleeve cooperating with the annular recess to provide a buier pocketjust prior to completion of counterrecoil of the Vgun tube.Y

5. Recoil mechanism fora gun, comprising: a gun tube; a tubular supportencasing the gun tube and mounting the gun tube for recoil andcounterrecoil; means between the outer peripheryVV of the gun tube andthe inner periphery of the tubular support forming an annular chamberfor containing recoil fluid; and including a coaxial annular. extensionprojecting from the counterrecoil end ofV the chamber toward the recoilend thereof and encircling the gun tube, the extension including abuffer element having an 'outer periphery formed as a frusto-conicalsurface diminishing in diameter in the direction of recoil and anadjacent annular portion of reduced diameter continuing rearwardly fromthe recoil end of 4said buffer element; and a buer sleeve encircling andconnected to the gun tube for recoil and counterrecoil therewith andpositioned in the chamber to closely encircle said buier element whenthe gun tube is in battery position saidrbuier sleeve Yhaving aninternal annular shoulder, said sleeve and shoulder codecreases in" voltube and mounting. thregun tube for recoil Vand counterrecoil;vmeans,lzufinveen the outer periphery. ofthe gunV tubegandthe innerperiphery.l rf the 'tubular support'. forming with saidsupport, a closedannular chamber for containing recoil fluid; and including a tubularmember projecting from the counterrecoil end of the chamber toward therecoil end thereof and encircling the gun tubefsaid tubular memberincluding a buffer element having an outer periphery formed-as afrusto-conical surface diminishing in diameter in the direction ofrecoil and vfurther including means forming an annular `recessrearwardly of and adjacent the recoil side of `saidlcuier element; and abuier sleeve encircling and connected to the gun tube for recoil andcounterrecoil therewith and positioned in the chamber toV closelyencircle said buffer element when the gun tube is in battery, saidbuffer sleeve having an annular inwardly. extending shoulder cooperablewithsaid sleeve and annular recess to provide a buffer pocket in which aquantity of buffer Yfluid is trapped,the volume of said pocket and thearea of escape` therefrom diminishing as said sleeve slides forwardlyover said frustoconical surface-in counterrecoil. i

'7. Recoil mechanism for a gun, comprising: a support; a gun tubemounted on the support for` recoil and counterrecoil; means on thesupportV forming a recoil cylinder -extendinggenerally in parallelismwiththe gun tube and adapted tcl-contain recoil fluid; means withinthecylinder at the recoilend thereofvforming an annular buffer elementhaving .its outer periphery formed as a section of a-cone4 diminishingin the direction of. recoil; meanson thebuffer element,v at the recoilsideV thereof, forming Aan adjacent coaxial annular portion lof.adiameter smaller than the smallest diameter-ofthe buler element; meansmounted in theA cylinderand connected to the gun tube for movement inunison therewith in recoil and counterrecoil-and including a buffersleeve positionedcoaxially with the buffer element, the buffer sleevehaving a generally cylindrical inner periphery that closely encirclesthe buffer elementwhen the gun tube is in battery and form-s with theadjacent annular portion, just prior to completion of counterrecoil,abuffer pocket adaptedto trap recoil fluid.

. H DONALD L. MEYERS. ARNOLD A. KESTER.

A Y Y REFERENCES CITED `The'followingreferences are of record in the leof this patent:

' UNITED srATEsrlrrENrs ,v1

.,Name- Number, Date 522,508 Canet f July 3, 1894 2,332,520 Y LuchtOct.- 26, 1943 2,358,340 Lucht Sept. 19, 1944 2,395,488 l Lucht s Feb.26, 1946

